can a spouse give power of attorney to someone else without his spouse permission? How can I find out if power of attorney has been given?

Questions about Power of Attorney abuse.
I was wondering what the law is in california on the following. If a person leaves a power of attorney for financial. to pay bills. The house was signed over to the power of attoeney so that if something happened to him it would not go into probate. the power of attorney has taken it upon herself to change the deed of the house to her being the soul owner and has taken a large loan out on the house and sold the house. Is this legal? There are still legal residents in this house. The house was never in danger of going into probate before she took out the loan. What can we do about this. It is very urgent. Any information would be greatly appriciated.

how many “power of attorney” documents can be filed for the same individual? Is it just one? Or can others file the same document with the state? We live in CA

emergency conservator
My mother is in the hospital and is unable to sign her checks to pay her bills. She has no power of attorney. I am on her savings account, but cannot sign her checks. What can I do without paying outrageous fees?